Caddo (kădˈō) [key], Native North Americans whose language belongs to the Caddoan branch of the Hokan-Siouan linguistic stock (see Native American languages). These people gave their name not only to the linguistic branch but also to the Caddo confederacy, a loose federation of tribes that in prehistoric times occupied lands from the Red River valley in Louisiana to the Brazos River valley in Texas and N into Arkansas and Kansas. Members, besides the Caddo, included the Arikara, the Pawnee, the Wichita, and others. The culture of these loosely knit peoples was similar. Generally they were sedentary, living in villages of conical huts, although they did raise horses. The culture of the Caddo proper was marked by a clearly defined system of social stratification and by a religion that closely regulated daily life. Some now reside on tribal land in Oklahoma. In 1990 there were 3,000 Caddo in the United States.
See J. T. Hughes, Prehistory of the Caddoan-Speaking Tribes (1968).